Signals from wireless transmitters, such as wireless access points providing wireless local area network (WLAN) connectivity and/or wireless base stations providing Wireless Wide Area Network (WWAN) connectivity (i.e., macrocells, picocells, microcells, and femtocells) can be used to determine the position of a mobile device. Some devices collectively referred to herein as “wireless transmitters” may also be configured to receive wireless signals, such as wireless access points and various types of WWAN base stations.
If a wireless transmitter is moved, position determinations using signals from that wireless transmitter can lead to erroneous position determinations for the mobile device. Detecting that a wireless access point, a wireless base station, or other wireless transmitter has moved is an important problem for mobile positioning techniques that rely on signals from these devices. Conventional approaches for determining whether a wireless transmitter has been moved are location dependent. For example, in one approach, signals received from a wireless transmitter by a mobile device at a known location can be used to approximate the location of the wireless transmitter. Another conventional approach uses location clustering to determine if a wireless transmitter has been moved. In the location clustering approach, signals from a group of wireless transmitters are received by a mobile device and looked up in an almanac to determine a geographic area associated with each of the wireless transmitters. If a particular wireless transmitter of this group is associated with a different geographic area than the rest of the wireless transmitters, then the wireless transmitter associated with the different geographic area has most likely been moved. In yet another conventional approach, an approximation of the location of a wireless transmitter can be determined based on an identifier of a cell coverage area in which the wireless transmitter is determined to be located. If the geographic area associated with the cell coverage area is inconsistent with a geographic area associated with the location of the wireless transmitter in the almanac information, the wireless transmitter has likely been moved.